Before a law clerk in Cook County Chief Judge Timothy Evans' office last month allegedly donned a robe and impersonated a judge, the race to unseat Evans was relatively restrained, with two judges waging a quiet challenge to Evans' 15-year rule.

But the scandal that broke out in the lower level of the south suburban Markham courthouse — where Judge Valarie Turner is suspected of allowing the clerk, Rhonda Crawford, to preside over three traffic cases — has given the race to become the county's top judge new urgency. Some longtime judges are trying to stoke discontent among colleagues in advance of Thursday's vote; others are seeking to undermine Evans with allegations of bungling and ham-fisted management.

The actions represent the most serious challenge to Evans' leadership since he became chief judge in 2001.

At stake is a position that holds great sway over one of the nation's largest judicial systems, exerting deep influence over cases ranging from traffic violations to murder trials.

"There's obviously a rebellion going on," said Dick Simpson, the former Chicago alderman who is now a political science professor at the University of Illinois at Chicago. "There's no doubt there's some pushback against Tim Evans. He's been there a very long time."

Evans, 73, is a former alderman who lost the 1989 mayoral race to Richard M. Daley. He faces challenges from Tom Allen, the former Northwest Side alderman who is now a judge, and Sandra Ramos, a former assistant state's attorney and criminal defense lawyer who was elected to the bench in 2010.

Ballots for the three-year term will be cast in secret Thursday. Cook County's 241 circuit court judges vote; 145 associate judges do not.

Races for chief judge tend to focus on management style dominating what are typically rather staid discussions of court procedures, much of it in "Dear Colleagues" letters rather than boisterous campaigning. Candidates sometimes go courtroom to courtroom seeking votes, and elected officials have been known to quietly lobby on behalf of a favored candidate.

Indeed, letters from Allen and Ramos seeking support from their colleagues are so buttoned-up it is hard to know a race is even on.

"It's a little like the old days of the machine. It's a pretty closed world," Simpson said. "A lot of it is whether the judges are satisfied with their own little world, and Tim Evans at the top. They're not looking at the overall question of whether there will be change to the system."

Evans, according to Simpson, has the "upper hand" in the election, in part because many judges owe Evans for their assignments.

There's obviously a rebellion going on. There's no doubt there's some pushback against Tim Evans. He's been there a very long time.— Dick Simpson, former Chicago alderman and UIC political science professor

Who controls Cook County's massive court system is important; an ineffective system can harm those who pass through it and cost taxpayers greatly. Allen and Ramos have said in letters and to colleagues they can run the system better than Evans.

Allen, who lost a primary election for state's attorney in 2008, declined to comment other than to say, "I care about the future of the courts."

Ramos drew a sharp distinction between herself and Evans and Allen. "Unfortunately, I'm not a politician. I'm an option," said Ramos, who was in private practice before she became a judge. "If they want same old, same old, let them have same old, same old."

While Allen and Ramos are seen as underdogs, Allen perhaps poses the greater threat to Evans' reign. Allen is widely known among his fellow judges and his family is connected through marriage to the storied Cullerton family, a force in city politics since the Great Chicago Fire in 1871.

Evans, in an interview Tuesday, brushed aside criticism from Allen and Ramos, saying neither has any experience as a supervisory judge.

"One of the things that needs to be clarified is that this is a coveted position," Evans said. "I'm being challenged by two people. I don't take it personally."

Evans, a Democrat like his two opponents, has run unopposed in three of the previous four elections. His last challenger was William Maddux, then the presiding judge of the Law Division who has since retired. Evans easily turned back Maddux's challenge.

Evans is a longtime figure in Chicago politics. He was elected to City Council in 1973, a position he held until Toni Preckwinkle, now county board president, narrowly defeated him in 1991. During his time on the council, he served as floor leader for Mayor Harold Washington, the city's first black mayor. After Washington died, Evans made his first bid for mayor when the council voted on his replacement, only to lose to Eugene Sawyer. Then, after losing his council seat, Evans ran for circuit court judge in 1992 and won. Nine years later, he ascended to chief judge when he defeated four challengers.

Today, Evans heads a sprawling system that has 13 courthouses, with about 1.2 million criminal and civil cases pending at any given time. Besides the 386 circuit and associate judges, Evans supervises close to 2,700 employees, and also heads the county juvenile temporary detention center and probation department. The court's 2016 budget is nearly $236 million, according to Pat Milhizer, a spokesman for the chief judge.

In a letter to judges, Evans touted his accomplishments, from technology upgrades to introducing new courts, such as the domestic violence court and specialty courts to hear veterans' issues, and matters involving mental health, drug abuse and sexual exploitation.

"While I respect any judge's right to run," Evans wrote, "I respectfully suggest that no other judge has more passion for improving our system of justice nor fought harder or longer to produce the results that I believe my leadership and experience have brought about."

Evans' long tenure has not been without controversy, much of it met with more than a little secrecy or inaction by him. A series of Chicago Tribune investigations has raised questions about how effectively Evans has managed the courts. A 2012 investigation, for instance, uncovered judges improperly hiding from public view potentially embarrassing cases involving politicians, athletes, wealthy businessmen and others.

The Tribune reported in 2013 that the Adult Probation Department had lost track of hundreds of convicts and had overlooked curfew violations and new crimes by offenders, some of whom went on to rape and kill. Not until three months later did Evans make leadership changes.

Another Tribune investigation into the probation department in 2014 found that an armed unit of rogue officers had allegedly violated probationers' civil rights. Evans hired a law firm to investigate the Tribune's findings, but he has refused to release the firm's report, or even to say if he had disciplined any employees or referred any wrongdoing to authorities.

That same year, the Illinois Supreme Court released a unprecedented report into how the court system under Evans handled criminal defendants. The report pointed out a lack of leadership and basic understanding of certain court services that led to people unnecessarily awaiting trial behind bars.

Evans said that years before the Supreme Court issued its report, he had been working to improve pretrial services and bond court.

The scandal out of the Markham courthouse is, perhaps, Evans' most embarrassing. Crawford was a law clerk and staff attorney in Evans' office who had won the Democratic primary for a seat on the bench and was running unopposed in this fall's general election.

Evans fired Crawford, who remains on the ballot for a position in the 1st Judicial Subdistrict, which includes the South Side and some south suburban villages. Evans reassigned Turner, the judge, to administrative duties, and apparently referred the matter to state commissions responsible for oversight of judges and lawyers. At the same time, the Cook County state's attorney's office has said it was conducting a criminal investigation.

Privately, and occasionally publicly, Evans' fellow judges have criticized his management style and leadership. Several judges said that Evans' office was slow to alert the sheriff's office after failing to take seriously a series of anonymous death threats made against five judges in 2015. Judges said Evans also was slow to respond to allegations from two female judges that they were sexually harassed by other judges.

Evans disputed those criticisms, saying he takes the safety of judges personally and does not tolerate a hostile work environment.

Judge Sheryl Pethers said in an email to fellow judges that Evans often plays favorites in promotions and courtroom assignments, a charge echoed — privately in most cases — by many judges. In a July 12 email, Pethers, who is retiring in early December, said she watched as less qualified judges were promoted, noting that "there are judges who regularly don't even come to work, but get to choose their courtrooms."

Judge Patrick Murphy also has written to his colleagues and to Evans, urging the chief judge to adopt changes in the courts — most of which would have the effect of loosening Evans' tight grip on the courts. Murphy suggested term limits for chief judge, more democratic input from judges, and a professional administrator to provide expertise on hiring and the budget. Evans, according to Murphy's emails, typically does not respond to his suggestions.

In a nod to the rampant politics in the court, Murphy also recommended that job openings on the bench be posted publicly.

"Rumors persist that qualified judges are at times overlooked for 'plum' assignments in favor of those who might be politically connected," he said. "The best way to put these rumors to rest is to post the job."

Evans, though, has cultivated support over the years.

Judge Robert Balanoff, for example, wrote to his colleagues to praise Evans, saying a change of chief judges could be disastrous.

"I fear a return to the storied past when judges were banished to distant courtrooms based on personal whims, prejudices and the decisions they made," he wrote.

Allen and Ramos suggest Evans has overstayed his welcome. In a Sept. 2 letter to colleagues, Allen said he would make the chief judge's office more transparent and accountable, and would support a limit of two three-year terms for chief judge. He pledged to hire court administrators to make the courts more efficient and said he would pursue improved relationships with the county board and other "government partners."

Ramos, in an Aug. 5 letter to colleagues, said she would improve communication between the chief judge's office and courtroom judges by scheduling regular meetings. She also said she would address what have become frequent complaints about assignments.

"What I have found to be my experience as a member of the judiciary in Cook County," Ramos wrote, "is the lack of communication between the Chief Judge and the majority of the judiciary."